Dear Folks,
I will add my thoughts to those of Wayne and Probir.
As a matter of history way back in the early 2000’s, when I was at Babcock & Wilcox, we installed a 600 MW PJFF with 8 meter bags at Hawthorne Plant in Kansas City which was, for a short time, the biggest PJFF in the world. We collaborated with Rothemuehle for the 8 meter reference & design. Many others followed this. After start-up, B&W soon tested in the lab 10 meter length and then installed an array of 10 meter test bags at Hawthorne to get actual field test data regarding cleaning, wear, permeability, etc. So, this R&D was well over ten years ago.
As Wayne points out, other commercial units using 9 and 10 meter bags were later put into operation. I will give the opinion that today, up to 10 meter bags is basically an industry accepted “standard” in the U.S., probably Europe - at least for OEMs that have those operating references.
And, as Wayne points out, it is quite likely that the next threshold being tested “right now” by leading competitors is likely 12 meters.
A problem with the initial testing at KCKR, referenced by Probir below and as presented at the time in the development meeting in Seoul, and by subsequent emails from Wayne, is that solid-data lab testing/evaluation necessarily needs to include a full length blowpipe arrangement with up to at least 16 test bags in array (as opposed to a single bag). Effectiveness at the bags closest – mid-way – furthest from the pulse valve.
And, yes, as Probir points out, with that developed lab design is the next step, being field demonstration of some sort – either pilot, or if we are able to sell & assume the risk, on a new unit somewhere (such as is Viet Nam in the 9.4 meter case).
One thought (I think I mentioned it in Seoul), is that perhaps we can accelerate the process if we are able to develop our design and implement a field test using a test compartment on the Viet Nam unit? We may likely need to use both the 9.4 meter bag length (or close) on the hopper perimeter bags due to lower clearances (or simply seal the tube sheet holes in the circumference of the tube sheet). Then we need to somehow monitor compartment flow vs. pressure drop over time, and periodically pull some used bags for standard battery testing (MIT flex, Mullen Burst, permeability, microscopic, etc.
My points/opinions are, in summary –
1. Competitor data acquisition is fine, but let’s not waste time on this. It can and should be ongoing. We don’t need to verify what is already known.
2. If we are to proceed with additional lab tests, we need to get on with it and do it meaningfully as mentioned above.
3. Hopefully the Viet Nam unit will verify the 9.4 meter KC design soon. We need also to verify a KC 10 meter design which will bring us to parity with leading competitors. We need also to push towards the 12 meter mark at the same time, or we will fall behind once again.
4. Time is NOT on our side in these endeavors.
Best regards,
Rich